Device for denicotinizing tobacco



April 5, 1938. LIPPMANN 2,113,114

DEVICE FOR DENICOTINIZING TOBACCO Original Filed May 11, 1936 7 7/ L udw z'y L L'p vmann Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE Original application May 11, 1936, Serial No. 79,097. Divided and this application April 15, 1937, Serial No. 137,116

1 Claim.

The invention relates to an apparatus in which tobacco is subjected to fermentation in a virulent alkaline liquor containing tobacco bacteria while admitting air up to complete removal of the nicotine.

The process is carried out as follows:

First, the removal of the nicotine is accomplished by the breeding of tobacco bacteria. Under the action of air the removing bacteria at first multiply slowly, and then more quickly, substance-exchanging products of high alkalinity being produced.

The nicotine removal only takes place to a considerable degree after the lapse of a certain time.

When once a first batch of tobacco has been subjected to the above mentioned treatment and has been denicotinized completely, the process according to the invention proceeds continuously. The liquor from the denicotinized tobacco batch is always used for the next batch, the liquor therefore becoming enriched with virulent bacteria. The separate tobacco batches are always introduced into the liquor as quickly as possible while the removal process is still in full operation, that is to say, while all the biological forces are still at the maximum of virulency so that any loss of active biological energy can be avoided.

Under particularly favorable conditions, i. e., with sufiicient supply of air and, preferably, high temperature, the alkalinity remains within allowable limits. When this is not the case there is added an organic acid, for example citric acid.

The acid is added preferably in the finest distribution, while the added air is also with advantage kept free from oil.

When the liquor is used a number of times, acid may be added immediately to each succeeding batch of tobacco. The quality of the denicotinized tobacco, especially taste and aroma, does not suffer by the new process, probably because the bacteria necessary for the removal of the nicotine are extremely predominant.

When a number of batches of tobacco have been denicotinized by means of the liquor, there remains a nicotine-free liquor strongly enriched with extractive substances. This may be added to those batches of tobacco which have lost mostly in extractive substances during the denicotinizing. These in general are the first tobacco batches.

The same tobacco liquor will thus serve frequently for denicotinizing until at a substantially prolonged duration of the denicotinizing process there is observed a deterioration of its activity.

The new process may, for example, be carried out as follows:-

In about 250 hours over 40 batches of a Kentucky tobacco of 3.2% nicotine content may be completely denicotinized, without the last batch having exceeded the average denicotinizing period at the last about 5 hours.

For carrying out the process there is preferably used a device wherein the air, and when acid is supplied also this, reaches all the tobacco parts uniformly distributed. In order that tobacco parts which are already nicotine-free need not remain exposed to the action of air (or acid) r until unfavorably located tobacco parts are denicotinized, an excess of acid is used. Further, it is necessary to prevent the tobacco from clogging together into a solid mass which cannot be penetrated by the supplied air and the injected acid.

Consequently the device for carrying out the new process consists of a movable receiving body for the tobacco leaves, for example a rotary drum, divided into sectors by partitions, which is located inside a fermenting vessel, containing the necessary quantity of water or liquor, under which receiving body are located distributing bodies for compressed air and in which fermenting vessel is provided a supply pipe for acid under pressure. Q

In many cases an immovable receiving device may suffice when provision is made for a uniform supply of air and acid to the tobacco by a sufiicient distribution of the tobacco, for example, on numerous, wide-meshed grids, which are located above one another in the form of terraces.

The accompanying drawing shows an example of construction of the device according to the invention.

Fig. 1 is an elevation of the invention with the fermenting chamber open.

Fig. 2 is a vertical section of the fermenting chamber, and Fig. 3 is a diagrammatic illustration of the compressed air pipe and of the air distributing body.

An electric motor I is coupled to a rotary compressor 2, which sucks air through a filter 3 and forces it through an oil separator 4. The acid container 5, which is provided with a level indicator 6, is subjected to pressure by means of a branch pipe 8 extending from the compressed air pipe 1. On the acid container is provided a charging funnel 9. In the fermenting chamber I D are provided two air distributing bodies II, to which lead four branch pipes of the air pipe I. The air distributing bodies consist of porous ceramic material, known per se. In the fermenting chamber and above the air distributing bodies II is located an apertured drum l3, adapted to be rotated by electric motor l2, which drum consists of separate sector-like chambers [4. The fermenting chamber has a removable closure wall l5.- Into the compressed air pipe 1 there leads an acid supply pipe I! which leads from the acid tank 5. I6 is an inspection glass provided in the pipe. From the pressure pipe 1 there is branched a pressure pipe I8 which terminates in a nozzle, directly above the nozzle of the acid pipe [1, in the compressed air pipe I. There is thus formed an injector l9 which sucks in the acid and atomizes it in the compressed air pipe I. The pipes l, 8, I l and I 8 are controllable independently of one another by the valves 26, 21, 28 and 29. It is important that the supply pipe for the acid terminates at a considerable distance from the receiving device for the material in the fermenting vessel.

The temperature at which the bacteria in general can have the most favorable action is about 37 C. In order to maintain the temperature uniform, the lower part of the fermenting chamber is provided with double Walls. The hollow space 24 serves for the reception of hot water. A thermostat provides for the maintenance of the desired temperature, which is determined by a thermometer 2|. The level of liquid in the fermenting chamber is indicated by a level indicator 22. Escaping gases pass through the flue 22, provided with a throttle valve 25, and if desired through a cooler for the purpose of condensing the escaping gases and aromatic substances.

The device is used as follows:

The tobacco is preliminarily moistened, preferably with liquor already nicotine-free. Into the separate removable sector 14 of the drum I3, is placed the tobacco, then the closure wall [5 is closed. The fermenting chamber i0 is supplied with water. The container 5 is filled with acid,

while the valves 21 and 29 are closed. After heating the fermenting chamber ill, the drum I3 is allowed to rotate and the compressor 2 is operated with the valves 26 and 28 open.

The air then passes through the distributing bodies H, in very fine division into the liquid of the fermenting chamber and there forms a froth which penetrates through the tobacco. After, for example, six hours the alkalinity of the tobacco and of the frothy liquor will have been increased considerably in consequence of the progress of the fermentation. Then, by opening the valves 21 and 29, the air can be charged with acid. The tobacco is thus, for example, after ten hours, free from nicotine and is removed from the container and dried.

Into the same liquor there is now placed a second batch of tobacco. In this case the air can be charged with acid from the commencement by opening the valves 21 and 29. By reason of the considerable enriching with bacteria, the time of the re-action is reduced at the further stages of the process and the tobacco is nicotine-free, for example, in six hours and at the third and further stages of the process, even in about five hours.

The liquor which remains at the end is mainly sprayed on the first tobacco part as this has given up the most extractive substances.

This application is a division of my application filed May 11, 1936, Serial No. 79,097.

What I claim is:

A device for denicotinizing tobacco comprising a fem'enting vessel, said vessel being adapted to receive the necessary quantity of alkaline liquor containing virulent tobacco bacteria, a rotary drum in said vessel, means for rotating said drum, partitions in said drum, said partitions dividing said drum into sector-like sections, said sections being adapted to receive tobacco in thin layers, distributing bodies for compressed air located underneath said drum, a supply pipe for acid under pressure having its delivery end located in said vessel, and means for supplying compressed air to said distributing bodies.

LUDWIG LIPPMANN. 

